Interlocking switch and signal device for railroads



(N70 Model.) 2 Sheets-Sheet 1..

-J. MARSTON, 3d. v Interlocking Switch and Signal Device for Railroads.

No. 240,153. Patented April 12,1881.

(No Model.) 2 Sheets-Sheet 2.

J. MA-RSTON, 3d. Interlocking Switch and Signal Device for Railroads.-No. 2 40 ,153'. v 4 Pat ented April 12,1881.

UNITED STATES PATENT OFFICE.

JOHN MARSTON, 3D, OF LOWER MERION TOWNSHIP, MONTGOMERY COUNTY,PENNSYLVANIA.

INTERLOCKING SWITCH AND SIGNAL DEVICE FOR RAILROADS.

SPECIFICATION forming part of Letters Patent No. 240,153, dated April12, 1881.

(No model.)

To all whom it may concern Be it known that I, JOHN MARSTON, 3d, acitizen of the United States, residing in Lower Merion township,Montgomery county, Penn- 5 sylvania, have invented certain Improvementsin Interlocking Switch and Signal Devices for Railroads, of which thefollowing is a specification.

My invention relates to certain improvements IO in the construction ofinterlocking switch and signal devices for railroads, the objects-of myimprovements being to simplify and cheapenthe mechanism employed, and toinsure a more direct action than usual of the switch and signal leversupon each other.

In the accompanying drawings, Figure l is a side view of a switch-standwith switch and signal operating levers constructed according to myinvention Fig. 2, a diagram showing the position of the rails andsignals when the levers are adjusted asin Fig. 1; Fig. 3, a side view ofthe switchstand, with the switch and signal levers in differentpositions from those shown in Fig. l; and Fig. 4,:1. diagram show- 2 5ing the position of the rails and signals when the levers are adjustedas in Fig. 3.

A represents the switch-stand, to which is pivoted the switch-operatinglever B, the short arm of which is connected to the switehrails,

as usual, and is enlarged so as to present three segmental faces, a, b,and d.

D and E are two levers hung to the stand A, and connected, by means ofthe ordinary arrangement of pulleys, levers, and cords or 3 5 wires, tosemaphore or other signals, the lever 5 ceed to describe.

When the various levers are adjusted to the positions shown in Fig. 1the switch-rails are set in line with the siding or branch track, as inFig. 2, the branch-line signal y, controlled by the lever E, is set atthe position of safety, and the main-line signal 00, controlled by thelever D, is set so as'to indicate danger. So long as the signaly,controlled by the lever E, remains in the position indicating safety theswitch-rails are locked in the position shown in Fig. 2, for the pin fotthe lever E bears against the face 61 of the lever B, and effectuallyprevents any movement of said lever tending to change the position ofthe switch-rails. At the same time the main-line signal, controlled bythe lever D, is locked in the position of danger, owing to the fact thatsaid lever D is prevented from moving by the contact of its pin a withthe face Z) of the lever B. Any movement of the lever E in the directionof the arrow, so as to unlock the switch-lever, will move the branchline signal from the safety position, and the switch-lever B is not freefrom the control of said lever E until the latter has been moved in thedirection of the arrow to its fullest extent, as in Fig. 3, by whichtime the branch-line signal g; has been set to the position indicatingdanger. The switch-lever B is then free to be moved in the direction ofthe arrow from the position shown in Fig. l to that shown in Fig. 3,this movement accomplishing three results--namely, the setting of theswitchrails to accord with the main line, the locking of the branch-linesignal y by the contact of the face b of the switch- 80 lever with thepin f of the lever E, and the releasing of the lever D by bringing intoline with the pin 0 of the latter the concentric face a of theswitch-lever. The moment the lever D, however, is moved in the directionof the arrow, Fig. 1, to change the main-line signal from the dangerposition to the safety position, the pin e, by contact with the face aof the switch-lever, locks the latter in position, and the switch-railsare secured. go

It will thus be seen that when the switchrails are set in line with thesiding or branch track the switch-lever is held, and the maintraoksignal or locked in the danger position by the lever E, and this stateof affairs continues as long as the branch-track signal y is in anyother than the danger position, and the branch-track signal andswitch-lever are similarly locked by the lever D when the switchrailsare adjusted in line with the main track.

Independent of the absolute safety thus attained, the main advantages ofmy invention are the simplicity and fewness of the parts employed, thecompactness with which the parts are arranged, and the direct action ofthe parts upon eaehother--that is to say, without the intervention ofthe usual cams, bars, levers, and springs.

I have shown the switch-lever combined with levers for operating bothmain and side track signals; but said switch-lever may be combined witha main-track signal-lever or a side-track signal only, if desired; andwhere a single switch requires to be combined with threesignal-operating levers the switch-lever may be secured to a rock-shaftcarrying a segmental arm similar to the short arm ofthe mainswitchlever, and the pin of the third signal-lever may actin connectionwith this additional arm of the switch-lever. In some cases, also, thesignallever may have enlarged arms with segmental faces, and theswitch-lever may carry a pin or pins for engaging with said segmentalfaces,

in place of the reverse arrangement before shown and described.

I claim as my invention 1. In an interlocking switch and signal de vicehaving a switch-lever and a signal-lever hung to a stand or support, thewithindescribed locking mechanism, comprising an enlarged arm of one ofsaid levers and a pin or projection on the other lever for en gagingwith the edge of said enlarged arm, all substantially as set forth.

2. The combination of the switch-lever B, the short arm of which hassegmental faces a, b, and d, with the signal-levers D and E, having pinsor projections for engaging with said segmental i'aces of the lever B,whereby both switch-levers and signal-levers are locked in position, asset forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN MARSTON, 3D.

WVitnesses:

JAMES F. ToBiN, HARRY SMITH.

